Effect of applied growth regulators on cone production in Douglas-fir, and relation of endogenous growth regulators to cone production capacity

1980 ◽  
Vol 10 (3) ◽  
pp. 405-414 ◽  
Author(s):  
E. E. McMullan
Keyword(s):  
Abscisic Acid ◽  
Growth Regulators ◽  
Growth Regulator ◽  
Production Capacity ◽  
Seed Orchard ◽  
Douglas Fir ◽  
Female Cone ◽  
Cone Production ◽  
Male Cone ◽  
Stage Of Development

Extracts of buds and young shoots of a good cone-producing clone of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) were tested for cone production effect on seed orchard Douglas-fir trees chosen for their history of poor cone production. Other metabolites, including gibberellin 4/7, arginine, and abscisic acid were also tested. Growth regulator levels in good and poor cone-producing clones of Douglas-fir were compared over the period of bud break and shoot elongation.No evidence was obtained for the presence of growth regulators critical to cone production in purified extracts from ramets of the good cone-producing clone. Applied gibberellin 4/7 increased male and female cone production. Crude extracts of a good cone-producing clone increased male cone bud production. Arginine and abscisic acid had no effect.Bioassays indicated that growth regulator levels in buds and young shoots changed greatly with stage of development but were similar in good and poor cone-producing clones.

scholarly journals Studies on the Pollination Characteristics and Pollination Level of Chinese fir Seed Orchard

2004 ◽  
Vol 53 (1-6) ◽  
pp. 7-11 ◽  
Author(s):  
Z. Zhuowen
Keyword(s):  
Accumulation Rate ◽  
Pollen Grains ◽  
Seed Orchard ◽  
Distribution Patterns ◽  
Chinese Fir ◽  
Female Cone ◽  
Bottom Part ◽  
Male And Female ◽  
Seed Orchards ◽  
Male Cone

Abstract Data from three seed orchards (Chongyang, Zhangle and Laoshan) and Lintian forest were used to study pollination characteristics, pollination level, pollen and ovule production in Chinese fir. The results show that male and female cones have their own distribution patterns within crowns. Male cones are located in the middle to top and female cones the middle to bottom part of the crown. Because of lower density of trees in seed orchard than that in a stand, female cones are distributed over the entire crown in seed orchard trees. Chinese fir male and female cones appear to be very well adapted for wind as the pollination mechanism. There is no difference in the number of pollen grains produced by one pollen sac among trees in the same clone, but there are differences between clones. There are differences between both clones and years in female cone number, male cone number and their ratio. The pollen accumulation rate during pollination should be 3 to 5 pollen grains/mm2 to ensure fertilization. The Chinese fir seed orchards in this study produced too much pollen and could be improved by stimulation of more female flowers in order to produce more seeds.

scholarly journals Reproductive Ecology of Male and Female Strobili and Mating System in Two Different Populations ofPinus roxburghii

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Chandra Mohan Sharma ◽  
Vinod Prasad Khanduri ◽  
Sunil Kumar Ghildiyal
Keyword(s):  
Mating System ◽  
Natural Populations ◽  
Production Capacity ◽  
Pollen Grains ◽  
Seed Orchard ◽  
Reproductive Period ◽  
Female Cone ◽  
Lower Altitude ◽  
Female Ratio ◽  
Male And Female

We studied several flowering traits, namely, male-female cone phenology, male-female cone production per tree, mating system, sex ratio, air-borne pollen grains and pollen migration, over four successive years in two different natural populations ofP. roxburghiifrom Garhwal Himalaya, India. Assessment of each trait mentioned except pollen dispersion was done by selecting five representative trees randomly in each population. The pollen migration was studied on naturally isolated source trees. The pollen trapping was done in all directions up to 2.5 km. The average reproductive period inP. roxburghiiwas 36 days with 3–5 days protandry. There were significant year and population effects for male and female cone output and pollen grains production per tree. In mass production year (1999), an average production of pollen cone per tree was estimated as42.44±8.32×103at lower altitude and28.1±0.89×103at higher altitude. The controlled pollination results in high level of outcrossing with 90% seed setting. We conclude that the high male-female ratio and tremendous pollen production capacity inP. roxburghiiindicate high male competition among trees within populations. The isolation strip of 600 m is considered minimal for the management of seed orchard.

scholarly journals Variation in Male Fertilities and Pairwise Mating Probabilities in Picea glauca

Genetics ◽  
1987 ◽  
Vol 116 (1) ◽  
pp. 141-152
Author(s):  
D J Schoen ◽  
S C Stewart
Keyword(s):  
Picea Glauca ◽  
Male Gamete ◽  
Seed Orchard ◽  
General Combining Ability ◽  
Frequency Data ◽  
Plant Populations ◽  
Cone Production ◽  
Male Cone ◽  
Male Gametes ◽  
Seed Crops

ABSTRACT Frequencies of multilocus male gametes in seeds collected from clones in several blocks of a white spruce seed orchard were analyzed as part of a 2-yr study of mating system variation in this species. Observed frequencies of male gamete types departed significantly from those expected assuming equal male fertilities among clones. Male gamete frequencies in seed crops were significantly heterogeneous among clones within blocks, and among blocks within clones. Clonal male fertilities were estimated from male gamete frequency data. These estimates were highly skewed, with a small proportion of the clones contributing male gametes to the majority of the seed. The estimates were significantly heterogeneous among clones within blocks, and among blocks within clones. Between-year variation in clonal male fertilities was also pronounced, with male fertilities of some clones changing by as much as three orders of magnitude. Clonal male fertility was significantly correlated with clonal male cone production in both years. These results are important with regard to assumptions made for the estimation of general combining ability, average genetic correlation among progeny from single parents, and expected response to selection in open-pollinated plant populations.

scholarly journals Effects of Light Intensity and Girdling Treatments on the Production of Female Cones in Japanese Larch (Larix kaempferi (Lamb.) Carr.): Implications for the Management of Seed Orchards

Forests ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1110
Author(s):  
Michinari Matsushita ◽  
Hiroki Nishikawa ◽  
Akira Tamura ◽  
Makoto Takahashi
Keyword(s):  
Light Intensity ◽  
Production Capacity ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Larix Kaempferi ◽  
Specific Response ◽  
Female Cone ◽  
Seed Orchards ◽  
Cone Production ◽  
Management Procedure

To ensure sustainable forestry, it is important to establish an efficient management procedure for improving the seed production capacity of seed orchards. In this study, we evaluated the effects of girdling and increasing light intensity on female cone production in an old L. kaempferi (Lamb.) Carr. seed orchard. We also evaluated whether there is a genotype-specific reproductive response to these factors among clones. The results showed that female cone production was augmented by girdling and increasing light intensity. There was a difference in the effectiveness of girdling treatment levels, and the probability of producing female cones increased markedly at higher girdling levels. At light intensities where the relative photosynthetic photon flux density was higher than 50%, more than half of the trees tended to produce female cones, even in intact (ungirdled) trees, and the genotype-specific response to light intensity was more apparent in less-reproductive clones. These findings suggested that girdling less-reproductive trees combined with increasing light intensity was an effective management strategy for improving cone production in old seed orchards.

Roles of endogenous and exogenous growth regulators in dormancy of Utricularia vulgaris

1979 ◽  
Vol 57 (24) ◽  
pp. 2750-2759 ◽  
Author(s):  
Robert D. Winston ◽  
Paul R. Gorham
Keyword(s):  
Abscisic Acid ◽  
Growth Regulators ◽  
Growth Regulator ◽  
Environmental Conditions ◽  
Vegetative Growth ◽  
Developmental Stages ◽  
Soybean Callus ◽  
Exogenous Growth ◽  
Endogenous Growth Regulator ◽  
Utricularia Vulgaris

The roles of endogenous and exogenous growth regulators on dormancy control of Utricularia vulgaris were investigated by extraction and bioassay of endogenous levels of four classes at various developmental stages and by measuring the effects of synthetic regulators on these stages. The bioassays used were oat coleoptile for auxins, abscisic acid and other inhibitors; lettuce hypocotyl for gibberellins; and soybean callus for cytokinins. Two weeks before turion formation and during innate dormancy abscisic acidlike and bound gibberellinlike levels were high while free gibberellinlike and auxinlike levels were low. Abscisic acid exogenously applied to actively growing plants rapidly induced turion formation even under noninductive environmental conditions. Kinetin rapidly and completely caused sprouting in innately dormant turions but would not promote continued vegetative growth. These plants formed new turions within 2 weeks of sprouting. During imposed dormancy, when turions rapidly sprouted, there was a low level of abscisic acidlike inhibitor and high levels of gibberellinlike and auxinlike compounds. Turions collected during this state could be maintained in a dormant condition by incubation with abscisic acid even at high temperatures which normally induce sprouting. During sprouting the endogenous growth regulator pattern was similar to that described for imposed dormancy. A model of the environmental and growth regulator factors which control dormancy is presented.

scholarly journals Precocious Male Cone Production associated with Low Nutrient Status in Clones of Pinus radiata

Nature ◽  
1965 ◽  
Vol 206 (4985) ◽  
pp. 739-739 ◽  
Author(s):  
G. B. SWEET ◽  
G. M. WILL
Keyword(s):  
Pinus Radiata ◽  
Nutrient Status ◽  
Cone Production ◽  
Male Cone

Gibberellin A4/7 enhances seed-cone production in field-grown black spruce

1988 ◽  
Vol 18 (1) ◽  
pp. 139-142 ◽  
Author(s):  
Rong H. Ho
Keyword(s):  
Vitamin E ◽  
Black Spruce ◽  
Seed Orchard ◽  
Shoot Elongation ◽  
Bud Burst ◽  
Lateral Shoot ◽  
Cone Production ◽  
Seed Cone ◽  
Vegetative Bud ◽  
Needle Primordia

Black spruce (Piceamariana (Mill.) B.S.P.) grafts growing in a seed orchard were sprayed with gibberellin A4/7, and grafts and trees in families growing in arboreta were sprayed with gibberellin A4/7 and (or) vitamin E from vegetative bud burst to the end of shoot elongation. Gibberellin A4/7 was very effective in promoting seed cones and 400 mg/L appeared optimal. Vitamin E at 1000 mg/L was not effective. Vegetative bud burst occurred in mid-May and shoot elongation ended in late June. Needle primordia were visible on the apices of newly formed buds at the end of June. Reproductive buds had fewer bud scales than vegetative buds. It appeared that potential reproductive buds terminated their bud scale initiation earlier. Gibberellin A4/7 application to promote seed-cone production should be carried out before bud-type differentiation. This coincides with the end of lateral shoot elongation.

The role of exogenous plant regulators in the dormancy of onion bulbs

1974 ◽  
Vol 82 (1) ◽  
pp. 113-116 ◽  
Author(s):  
M. Abdel-Rahman ◽  
F. M. R. Isenberg
Keyword(s):  
Abscisic Acid ◽  
Growth Regulators ◽  
Maleic Hydrazide ◽  
Rest Period ◽  
Storage Period ◽  
Inhibitory Effect ◽  
Onion Bulbs ◽  
Subsequent Application

SUMMARYExperiments were conducted to study the effect of plant injection with growth regulators on the dormancy of onion bulbs cv. Elba Globe. Application of abscisic acid induced early senescence of the leaves and prolonged the rest period of the bulbs. This effect was partially overcome by subsequent applications of gibberellin, auxin or cytokinin and totally overcome with the application of a mixture of the three hormones. Maleic hydrazide application prolonged the rest period by inhibiting both sprouting and rooting of the bulbs throughout the storage period. This inhibitory effect was not overcome by the subsequent application of auxin, gibberellin, kinetin, or their combinations. Ethephon application increased rooting of bulbs and partially overcame the effect of abscisic acid on dormancy.

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